New nanocomposite-graphene pastes based stochastic microsensors

Three new stochastic sensors based on metal nanocomposites-graphene pastes modified with protoporphyrin-IX were designed. PPAR-γ was chosen as model analyte to prove the stochastic behavior of the sensors. The sensor based on PIX/graphene-Au-3 showed the highest sensitivity for the assay of PPAR-γ (1.94 × 10 7 s −1 g L −1 ) and the lowest determination limit (20 pg mL −1 ). The sensors were stable for more than three months (RSD values of their sensitivity did not exceeded 1.0%). They could be reliably used for the assay of PPAR-γ in cerebrospinal liquid with recovery values higher than 97.0%. Stochastic sensors based on metal nanocomposites-graphene pastes modified with protoporphyrin-IX were used for the assay of PPAR-γ in cerebrospinal liquid.